GOLD COAST, Australia (AP) — A sore back has already caused problems for Missy Franklin at the Pan Pacific championships, with the world champion missing qualification for the final of the 200-meter freestyle.

The 19-year-old Franklin, who won six gold medals at last year’s world championships, swam in the morning preliminaries of the 200 free on Thursday but had the third-fastest time of the U.S. swimmers and failed to qualify for the night final.

With a quick turnaround, she returned to swim the 100 backstroke and qualified for the final as the fastest American.

Franklin had back spasms during practice Tuesday and had been in doubt for the meet, being held in an outdoor pool on Australa’s Gold Coast.

Franklin, who won both the 100- and 200-meter backstroke at the 2012 Olympics, was originally scheduled to swim the 100 and 200 freestyle, 100 and 200 backstroke and relays at the Pan Pacs.

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